I just got back from the doctor and he thinks it's a pulled muscle because of the way it hurts all the way across my ribs and I had forgotten until late last night that when I was doing Chrome's hooves the other day that I almost rolled my ankle so I let myself fall. I landed hard on my hands and knees and fell to my hip which could have definitely wrenched my back. He gave me a muscle relaxer to take at night so I just have to get through today and I'll have three days off to heal. Obviously if it doesn't get better I'll demand an xray, but my gut instinct is that it's just a pull. I've never had back problems before.
I also asked them to check my thyroid levels (because I've been exhausted and lost weight again) and we're going to check my vitamin D levels (because my mom's are very low) and my iron levels. So I'm hoping we'll find out what's going on and by this time next week I'll be all better. :) Thanks for your kind words over my post last night. I knew I'd get some advice because of how prevalent back injuries seem to be. You guys are awesome!